Engineering Commons^™

Progress Towards The Study Of Self-Repaired Nanocomposites: Generating Single Chirality Species Of Metallic Single Walled Carbon Nanotubes, Chunxu Chen

All ETDs from UAB

This thesis is dedicated to exploring the separation technique of single wall carbon nanotube (SWNTs). Limited by the commercial synthesis method and required by the self-repaired nanocomposites project, the SWNTs was separated by length and chirality. In length separation, the density gradient ultracentrifugation (DGU) technique was applied. We have optimized the processing procedure for sorting single wall carbon nanotubes by length. A good length distribution was obtained from ~600nm to ~60 nm by layers. A new approach, aqueous two-phase separation (ATPS), was used for metallic-semiconducting separation of SWNTs. We studied the surfactants’ influence in a two-phase system, polyethylene glycol (PEG) …

Endothelialization Of Microchannels In A Three Dimensional Breast Cancer Tumor Surrogate Model, Derek Van Vessem

All ETDs from UAB

Drug discovery and testing commonly employs two dimensional (2D) human cell line monolayers for lead compound identification before becoming a candidate therapy to be studied in animal models. Culturing cells in 2D produces a homogenous disbursement of nutrients and anticancer-therapeutics resulting in a response specific to 2D that does not necessarily translate to a three dimensional (3D) response. This method unfortunately distorts the in vivo human drug response. The lack of physiologic dimensionality in 2D cell monolayers distort cellular responses relative to 3D systems that can be attributed to minimal drug approvals. Oncology drugs are the least successful with only …

Effects Of Stored Red Blood Cells On The Components Of The Lung-Capillary Membrane, Kaitlyn S. Ryan

All ETDs from UAB

Trauma is the leading cause of death for Americans between the ages of 1 and 44. Implementation of massive transfusion protocols has improved early mortality due to traumatic hemorrhage; however, long-term complication rates associated with hemorrhagic shock remain high due to the development of multiple organ failure. In particular, resuscitation with large volumes of stored red blood cells (RBC) introduces high concentrations of free heme, which contributes to the development of acute lung injury (ALI) after trauma. Angiopoietin-2 (Agpt-2) is a mediator of trauma-related lung injury, but the effect of RBC storage-derived free heme on Agpt-2 regulation is unknown. The …

A Comparison Of Traditional And Adaptive Comparative Judgment Assessment Techniques For Freshmen Engineering Design Projects, Scott R. Bartholomew, Greg J. Strimel, Andrew Jackson

Faculty Publications

This article examines the use of an alternative form of assessment for engineering design projects called adaptive comparative judgment (ACJ). The researchers employed an ACJ tool to evaluate undergraduate engineering student design projects in an effort to examine its’ reliability, validity, and utility in comparison with traditional assessment techniques. The ACJ process employed multiple judges to compare the design artifacts of 16 first-year engineering majors. The authors conducted an analysis of the reliability and validity of the ACJ method compared to the traditional rubric used to evaluate the project and the performance data of each student’s design prototype. For these …

Drive-By Bridge Damage Inspection And Monitoring, Ahmed Elhattab

All ETDs from UAB

Recently, drive-by bridge inspection has become an intriguing topic in the bridge health monitoring domain. The technique utilizes indirect measurements from the suspension system of a vehicle passes over the bridge to infer the bridge structural health condition. A number of studies have given confidence, hypothetically, in the feasibility of the approach in detecting, quantifying and localizing the damage. However, there is a scarcity of work investigating the fidelity of this technique to full-scale field applications. Whereas the wide number of uncertainties that governs the vehicle bridge interaction dynamics could significantly impact hypothetical techniques when applied in the field, the …

Role Of Diminished Pulsatility From Continous Flow Ventricular Assist Devices On Small Vessel Endothelial Dysfunction, Thomas Haglund

All ETDs from UAB

Ventricular assist devices (VADs) are standard therapy for patients with advanced heart failure that is refractory to medical therapy. VADs can be categorized as pulsatile flow VADs (PF-VADs) and continuous flow VADs (CF-VADs). Both PF-VADs and CF-VADs are similarly effective in providing hemodynamic benefit and improving the quality of life and functional capacity of patients. CF-VADs are preferred over the PF-VADs due to advantages such as compact size, reliability, energy efficiency, installation and operation. However, CF-VAD support results in non-physiological diminished arterial pressure and flow pulsatility. Using the endothelial cell culture model (ECCM), we previously established that diminished pulsatility resulted …

Prohealing Multifunctional Endothelium Nanomatrix Coated Stents, Grant Alexander

All ETDs from UAB

Cardiovascular disease is currently the number one cause of death in the United States, and indeed, worldwide. Stents are the most commonly implanted devices used to treat cardiovascular disease. Bare metal stent use remains limited by relatively high rates of in-stent restenosis, a re-narrowing of the artery after stent deployment. Restenosis within stents is a result of neointimal proliferation of smooth muscle cells and the accom-panying extracellular matrix deposition in response to vessel injury. To address this, drug-eluting stents have been developed to reduce restenosis; however, difficulties with late stent thrombosis, inflammation, and poor re-endothelialization remained. Thus, alt-hough numerous approaches …

Wireless Communication Systems Modeling And Design Using Communication Theory, Saleh Saeed S Allehaibi

All ETDs from UAB

The demand for reliable wireless communication systems has dramatically increased in recent years. Developing new methods, that exploit limited resources of power and bandwidth, is necessary to satisfy such a huge communication demand. Thus, the multiple-input multiple-output (MIMO) system is considered an efficient solution for wireless communication systems. MIMO system provides high data rates by exploiting the spatial domain under the constraints of limited transmit power and bandwidth. One of the MIMO systems transmitting strategy is the Space-Time Block Codes (STBCs) that exploits transmit diversity and high reliability. Also, the least action principle (LAP) of information theory seeks optimal effectiveness …

Organic Inkjet-Printed Carbon Nanotube Field Effect Transistor Dc Model For Sensing Applications, Steven Gardner

All ETDs from UAB

A technological renaissance is underway, allowing large-area displays, paper thin sensors, flexible electronics and printable circuits. A new circuit manufacturing technique has the potential for a plethora of promising applications from non-invasive biosensors to radio-frequency identification tags (RFIDs). Functional layers are printed onto a planar substrate by inkjet printers retrofit with conductive inks, resulting in the inkjet-printed circuit (iPC). Functional RLC components have been designed with relatively high reliability, paving the way for fully printed passive and active analog filters. The main electrical component being researched to meet industrial standards is the printed transistor. This thesis establishes a digital model …

Automated Image Analysis Of Ternary Eutectic Microstructures, Elizabeth Gauntt

All ETDs from UAB

Detailed descriptions of complex microstructures are necessary for detailed understanding of their production and consequences. However, there is no consensus on how to characterize microstructures with even three phases. Invariant ternary eutectics have greater complexity than binary eutectics, require more variables to completely describe, may change morphology due to processing conditions, and are deceptively difficult to characterize automatically. For these reasons, a program has been developed which can partition a ternary image into regions of its three phases (using a segmentation and correction process prescribed by the user), then return an assortment of measurements characterizing the microstructure. These measurements have …

Modeling And Experimental Study Of Fluid Dynamics Of Sand Granular Flow For Core Making, Jun Ge

All ETDs from UAB

Sand core making is one of the essential parts of the manufacturing process in the metal casting industry. Blowing a sand granule mixture on the core machine determines the quality of the core. This filling process under air pressure can be simulated with commercial numerical packages for granular flow modeling. However, many areas are still unclear for further establishing the numerical-to-practical correlation in industrial-scale processes where specific granule materials and conditions are presented. Continuum and discrete approach are popular methodologies to simulate granular flow. In continuum method, coefficient of restitution (COR) is introduced as a scalar parameter to represents the …

Preliminary Thermal And Stress Analysis Of An Electrical Connection Acting As A Thermal Dam On A Nitinol Wire, Lloyd D. Balfour

All ETDs from UAB

The type of actuator studied in this paper is a joule heated shape memory alloy (SMA) thermal actuator. The electrical connections of the actuator electrically partition the SMA in a binary fashion with the section either fully actuated or not. This method creates a digital actuator rather than an analog actuator. Heat from an energized partitioned section will conduct to adjacent partition sections which may partially activate the adjacent partitioned sections. The connections will act as heat sinks to mitigate this effect. The thermal SMA actuator is referred to as a Diginol actuator. This paper includes the thermal analysis of …

Wear, Corrosion, And Micromotion In Retrieval And Autopsy Components Of Tkr, Heath Mitchell Baskin

All ETDs from UAB

Total knee replacement (TKR) is used to remedy end-stage joint deterioration. Despite advancements in TKR design, thousands of patients still experience aseptic loosening and the revision surgeries that follow. Wear and corrosion processes can lead to the harmful production of debris, causing osteolysis in the periprosthetic space. This study seeks to quantify the relationships of wear, corrosion, and micromotion as it relates to aseptic loosening in TKR. 17 TKR devices harvested at revision surgeries and 6 necropsy devices available through UAB’s retrieval program were scored for wear and inflammatory cell-induced corrosion (ICIC). All devices were implanted ≤ 10 years. All …

A Computational Approach To Analyze Vortex Induced Vibration For A Flexible Riser, Ibrahim Bilgin

All ETDs from UAB

ABSTRACT Vortex shedding is an oscillating flow behind blunt bodies when fluid flows past it. One of the consequences of vortex shedding is the vortex-induced vibrations (VIV), which happens in numerous engineering structures such as bridge, heat exchangers, marine cables, electrical power lines, and risers in petroleum production. A critical application of VIV is the risers used in petroleum industries, which connects between sea surface and sea base. A failure of risers and platforms can result in enormous economic and catastrophic environmental problems. Therefore, understanding VIV is essential to estimate fatigue damage of the offshore systems. This thesis describes a …

Multi-Generation Modeling Based On A Natural Gas Driven Internal Combustion Engine, Nnamdi Gabriel Okafor

All ETDs from UAB

Science and technological advancement, environmental pollution, government policies and rising energy costs have long since begun redefining the way power is generated, distributed and utilized. Considering the much higher standards relative to common practices, distributed energy power generation has proven to be a viable alternative to centralized power generation due to the many advantages such as energy generation and control independence, lower greenhouse emissions and significant reduction in transmission losses. This research considers a natural gas-powered internal combustion engine with trigeneration capabilities or combined cooling heating and power (CCHP) as well as renewable energy incorporation including solar panels and possibly …

Characterization Of Top Three Nonfatal Occupational Injuries, 2012-2014, Levent Onat

All ETDs from UAB

Characterization of nonfatal occupational contact with object or equipment injuries, falls on same level injuries, and overexertion injuries involving outside sources that are considered as the top three occupational injuries comprise this study. The injury data from 2012 to 2014 have been obtained from the National Electronic Injury Surveillance System - Occupational Supplement (NEISS-Work) which collects the data from a national probability-based sample of U.S. Hospital Emergency Departments (EDs). The data for selected variables were queried for the three most-occurring injury categories by using Work-Related Injury Statistics Query System (WORK-RISQS). Worker demographics and their impacts on injury characteristics have been …

Through Thickness Property Variations Of Compression Molded Long Glass Fiber Reinforced Polypropylene With Different Thicknesses, Vikas Patel

All ETDs from UAB

Composite materials are on the verge of becoming primary materials choices for many applications due to their promising features of achieving high strength and stiffness and lightweighting of many components. Thermoplastic matrix composites have been gaining favor due to their superior toughness and energy dissipation properties coupled with corrosion resistance and ease of processing. Long fiber thermoplastics (LFTs) are a class of composites, which contain discontinuous reinforcements at a length above the critical fiber length for efficient load transfer to the reinforcement. These materials are gaining steady favor due to their positive aspects of tailorable properties, intrinsic recyclability, high specific …

Efficiency Of Structurally Integrated Surface Articulation (Sisa) Panels For Structural Engineering Applications, Feyza Nur Yildirim

All ETDs from UAB

The objective of this project is to investigate the efficiency of a newly developed structurally integrated surface articulation (SISA) building system for encapsulating an extensive range of specific and multi-purpose functions such as exterior panels for buildings and solar panels for structural engineering applications. SISA is a modular system, consisting of a 3-space, dynamically configured, geometrically need renewal surface panels that are internally supported by a "wire-frame" space frame structure. The appropriate articulations to these different methods will vary from one element to another. Surface articulation development is an efficiently developing issue, especially in continuing research on new generational frame …

Design And Development Of An Affordable Telemetry System For Navigation Of Autonomous Vehicle, An Liu

All ETDs from UAB

Nearly 1.3 million people die in road crashes each year, which is on average 3,287 deaths a day. An addition to the death toll, another 20-50 million are injured or disabled [1]. These are the huge deal of damage to the human’s body. Therefore, in this thesis, we implement autonomous navigation and find the safe path for travel, in which the vehicle can find the most feasible path and drive along this path independently. In order to gain insight and have an opportunity to investigate further on autonomous vehicles field, we define the aim of this project to design, develop, …

Utilization And Environmental Durability Of Advanced Composite Design Of Seismic Foundation For All-Soil Site Classes, Qian Huang

All ETDs from UAB

Three bridge sites in Alabama are investigated for potential seismic-foundation retrofit. A new seismic foundation method that uses Fiber Reinforcement Polymer (FRP) to strengthen the head of pile (FSHP) is proposed. Two FRP specifically, Carbon-Fiber Reinforced Hybrid-Polymer-Matrix Composite (CHMC) and Carbon Fiber Reinforced Polymer (CFRP), are used in this new seismic retrofit method. Finite Element Seismic simulation (FEM) is used to examine the seismic retrofit performance of bridge foundation. Both CHMC and CFRP FSHP retrofitted piles are shown to survive the design-earthquake, but it is shown that CHMC, which is a wrap / epoxy / spray-on material, provides markedly better …

Characterization Of Pyrolysis Products From Fast Pyrolysis Of Live And Dead Vegetation Native To The Southern United States, Mohammad-Saeed Safdari, Mahmood Rahmati, Elham Amini, Joel E. Howarth, Jansen P. Berryhill, Mark Dietenberger, David R. Weise, Thomas H. Fletcher

Faculty Publications

Prescribed burning (controlled burning) is used to decrease accumulation of combustible materials and reduce impact of uncontrolled wildland fires. Prescribed fires are often used to burn undergrowth in Southern forests of the United States. In order to improve prescribed fire application, accomplish desired fire effects, and limit potential runaway fires, an improved understanding of the fundamental processes related to combustion of heterogeneous fuel beds of live and dead fuels is needed. The initial processes of combustion involve pyrolysis and ignition. During this research, fast pyrolysis of 14 live and dead (biomass) plant species which are native to the Southern United …

Effect Of Different Alumina Supports On Performance Of Cobalt Fischer-Tropsch Catalysts, Thomas H. Fletcher

Faculty Publications

Four identically-prepared 20 wt% cobalt/0.15 wt% ruthenium Fischer-Tropsch catalysts, supported on different aluminas, were synthesized by incipient wetness impregnation, characterized, and compared based on their performance under standard Fischer-Tropsch synthesis conditions. Three alumina supports were obtained from commercial sources (Sasol, St. Gobain, and Alfa Aesar), while the fourth was made using a published technique that included 5 wt% silica. The silica-stabilized alumina catalyst produced superior Fischer-Tropsch rates of 49 mmol CO/gcat h, compared to the other catalysts on the commercial supports with rates of 26–39 mmol CO/gcat h. The improved performance of the silica-stabilized alumina support compared to the commercially …

Development Of Bioreactors For Comparative Study Of Naturalattenuation, Biostimulation, And Bioaugmentation Ofpetroleum-Hydrocarbon Contaminated Soil, Mohammad-Saeed Safdari, Hamid-Reza Kariminia, Mahmood Rahmati, Farhad Fazlollahi, Alexandra Polasko, Shaily Mahendra, W Vincent Wilding, Thomas H. Fletcher

Faculty Publications

Bioremediation of soil and groundwater sites contaminated by petroleum hydrocarbons is known as a technically viable, cost-effective, and environmentally sustainable technology. The purpose of this study is to investigate laboratory-scale bioremediation of petroleum-hydrocarbon contaminated soil through development of eight bioreactors, two bioreactors for each bioremediation mode. The modes were: (1)natural attenuation (NA); (2) biostimulation (BS) with oxygen and nutrients; (3) bioaugmentation (BA)with hydrocarbon degrading isolates; (4) a combination of biostimulation and bioaugmentation (BS-BA). Total petroleum hydrocarbons (TPH) mass balance over the bioreactors showed about 2% of initial20,000 mg kg-soil−1TPH was removed by advection due to synthetic groundwater which was flow-ing …

Dna Sequence Mediates Apparent Length Distribution In Single-Walled Carbon Nanotubes, Mohammad Moein Safaee, Mitchell Gravely, Caroline Rocchio, Matthew Simmeth, Daniel E. Roxbury

Chemical, Biomolecular, and Materials Engineering Faculty Publications

Single-walled carbon nanotubes (SWCNTs) functionalized with short single-stranded DNA have been extensively studied within the last decade for biomedical applications due to the high dispersion efficiency and intrinsic biocompatibility of DNA as well as the photostable and tunable fluorescence of SWCNTs. Characterization of their physical properties, particularly their length distribution, is of great importance regarding their application as a bioengineered research tool and clinical diagnostic agent. Conventionally, atomic force microscopy (AFM) has been used to quantify the length of DNA-SWCNTs by depositing the hybrids onto an electrostatically charged flat surface. Here, we demonstrate that hybrids of DNA-SWCNTs with different oligomeric …

Real Time Evaluation Of Tissue Optical Properties During Thermal Ablation Of Ex Vivo Liver Tissues, Vivek K. Nagarajan, Venkateswara R. Gogineni, Sarah B. White, Bing Yu

Biomedical Engineering Faculty Research and Publications

Complete ablation of liver tumors is vital for minimizing the risk of local tumor recurrence. Accurately identifying the hallmarks of tissue necrosis during thermal ablative therapies may significantly increase the efficacy of ablation, while minimizing unnecessary damage to the surrounding normal tissues or critical structures. Light propagation in biological tissues is sensitive to the tissue microstructure and chromophore concentrations. In our previous studies, we found that the wavelength (λ) averaged liver tissue absorption coefficient μ_a and reduced scattering coefficient μ_s’ change significantly upon heating which may be used for assessment of tissue damage during thermal …

Analysis Of Eeg Coherence During Active Suppression In Patients With Tourette's Syndrome, William Kalusche

Honors Theses

One of the first studies that investigated quantitative qualities of Tourette syndrome (TS) found that during active suppression of tics TS patients exhibit increased coherence in the alpha frequency (Serrien, Orth, Evans, Lees, & Brown, 2005). In this study, we attempted to validate the previous literature to allow for future research into the role played by increased coherence during active suppression. Our findings,however, showed that there was no significant increase in coherence between active suppression and rest. The findings in this study, along with previous literature, may suggest that TS patients with comorbid obsessive-compulsive disorder (OCD) affect the alpha power …

A Case Study On The Design And Optimization Of An Ethylbenzene Production Plant, William Grafton Peaster

Honors Theses

This thesis will detail two goals of my capstone design project. The first goal is to simulate a given base case of a vapor phase reaction ethylbenzene production facility in PRO/II simulation software and discretely optimize the process in order to increase the profitability of the plant. The second goal is to develop a base case process flow diagram, stream tables, utility tables, and equipment tables for an ethylbenzene facility with liquid phase reactions. The base case simulation and optimization is a group task with my assigned group members in Ch E 451. The first part of this study looks …

Opioids Delay Healing Of Spinal Fusion: A Rabbit Posterolateral Lumbar Fusion Model, Nikhil Jain, Khaled Himed, Jeffrey M. Toth, Karen C. Briley, Frank M. Phillips, Safdar N. Khan

Biomedical Engineering Faculty Research and Publications

Background Context

Opioid use is prevalent in the management of pre- and postoperative pain in patients undergoing spinal fusion. There is evidence that opioids downregulate osteoblasts in vitro, and a previous study found that morphine delays the maturation and remodeling of callus in a rat femur fracture model. However, the effect of opioids on healing of spinal fusion has not been investigated before. Isolating the effect of opioid exposure in humans would be limited by the numerous confounding factors that affect fusion healing. Therefore, we have used a well-established rabbit model to study the process of spinal fusion healing that …

Use Of A Dynamic Balance System To Quantify Postural Steadiness And Stability Of Individuals With Lower-Limb Amputation: A Pilot Study, M. Barbara Silver-Thorn Phd, Joel Kempfer, Alyssa J. Schnorenberg, Brooke Slavens

Biomedical Engineering Faculty Research and Publications

Introduction Despite rehabilitation and gait training, the gait of individuals with lower-limb amputation is often asymmetric and falls and/or fear of falling are common. Clinical assessments of balance and stability include the Berg BalanceScale and the Dynamic Gait Index. Biomechanical assessments, conducted largely in research laboratories, are more objective, quantitative, and may provide greater resolution. These biomechanical measures include postural sway during both unilateral and bilateral standing tasks and the dynamic postural response to applied or volitional perturbations. The objective of this study was to investigate the utility of a dynamic balance system, a relatively new clinical tool incorporating dual …

Infographic : Engineers And Athletes: Career Opportunities And Average Earnings, Mckenna James, Leroy Long Iii

Publications

In this infographic, the average earnings for athletes and engineers are displayed. For a variety of sports, the average yearly salary, average career length, and average career earnings are collected. In a similar way, the average mid-career salary and average career earnings are shown for multiple engineering disciplines. In addition, a series of facts show the professional opportunities for engineers and athletes. Based on this infographic, engineering is a more viable career choice and competes with the career earnings of professional athletes. This infographic is not meant to discourage playing sports, but to encourage youth and young adults to view …